There have been a number of accidents aboard warships that resulted in a large number of casualties and loss of platforms and systems and munitions, which has led to the requirement of providing weapons/munitions that have a reduced response to potential hazard stimuli. The subject of Insensitive Munitions (IM) has become an important one in the design, procurement, storage and deployment of any weapons system that employs propellants or explosives, that is most weapons. There is now a general requirement to design main charges, booster charges, explosive trains, rocket motors and gun propellant charges such that, when exposed to a disruptive threat, they respond as benignly as possible. Therefore, ideally they should give rise to a burning reaction, rather than a high order explosive event or a detonation. In this way it is hoped to avoid the generation of a shockwave or of damaging fragments that would adversely affect other weapons stored in the proximity. By so doing, the hope is that fratricidal events or “chain reactions” can be avoided.
By the term “munition” as used herein is meant any casing that carries a high explosive material in the form of a warhead. The munition may also comprise other energetic materials that are used to deliver said warhead, such as bombs, rockets, or any similar device.
There are many devices that are fitted/incorporated onto munitions to reduce the effects of external hazard events. However, many of these introduce their own drawbacks, such as adding parasitic mass, or even adding additional energetic materials which are designed to react against certain hazard events. It is therefore desirable to provide a means of reducing the likelihood of a detonative event when part of the warhead is subjected to a detonative blast or fragment/bullet attack which would otherwise cause detonation of the whole munition, without reducing the effectiveness and output of the munition when deployed in its normal mode of use.